A potboiler is like when someone is cooking a big pot of soup or stew on the stove. The heat from the stove makes the pot get really hot and the soup or stew boils inside. In the same way, a potboiler is a book or movie that is really easy to make and doesn't take a lot of effort. It's not always the best quality, but people still enjoy it because it's entertaining. Imagine reading a book where the story is predictable and the characters are not very interesting, but it's still fun to read because it's exciting and easy to understand. That's basically what a potboiler is. It's something that doesn't require a lot of thinking, but it still makes you feel good.